What it means: The Rams improved to 4-0-1 against the NFC West with a victory carrying long- and short-term implications for the division. St. Louis served notice again that it's going to be a player in the division for years to come under coach Jeff Fisher. And while a playoff push isn't likely given the Rams' 5-6-1 record, they at least opened the door for 7-5 Seattle to challenge the 8-3-1 49ers atop the division. This outcome will also provide an opportunity to revisit the 49ers' decision to replace quarterback Alex Smith with Colin Kaepernick. That will likely be the case every time San Francisco loses a game for the remainder of this season.

What I liked: Both defenses played well from the beginning. The Rams held the 49ers to their lowest point total since a game against Seattle in Week 7.

Kaepernick and Ted Ginn Jr. combined for a key fumble, but Kaepernick bounced back with the 50-yard run. He scrambled to convert on third down earlier in the game. That was good for the 49ers, obviously, but it also reflected good pass defense by the Rams. And when the Rams finally did drive deep into 49ers territory, San Francisco made a fourth-and-goal stop to preserve its 7-0 lead.

Frank Gore broke a 23-yard run for the 49ers and scored the only touchdown of the first half. Teammate Aldon Smith collected another sack, giving him 17.5 this season and more through two seasons than any player since the NFL began tracking sacks in 1982.

Rams rookie Janoris Jenkins, who scored two touchdowns against Arizona last week, collected another one when he returned the Kaepernick fumble to the end zone. And when the Rams' Sam Bradford found Lance Kendricks on the two-point conversion, the game was tied 10-10.

Rams rookie Greg Zuerlein made the tying 53-yarder and the winning 56-yarder to continue a remarkable first season.

What I didn't like: The Rams couldn't score in a goal-to-go situation early in the third quarter. This was a rare chance for the Rams to get points. Going for it on fourth down was understandable. The strategy has worked for the Rams in recent weeks. Failing to get points there really hurt, though.

The 49ers took a safety when officials determined Kaepernick did not get the ball past the line of scrimmage on a pass from the end zone. Replays seemed to show the ball traveling past the line, however. That might have been questionable call. The ruling was a bit confusing. However, as Fox analyst Mike Pereira explained, the line of scrimmage extends out of bounds for the purposes of grounding penalties.

Niners kicker David Akers missed a 51-yard attempt at the game winner in overtime. Akers has been playing hurt and his long-range kicking in particular has suffered.

What's next: The 49ers are home against Miami in Week 14. The Rams visit the Buffalo Bills.